Pressure gauge



June 10, 1930. E. A. IYLEMAN 1,763,354

PRES SURE GAUGE Filed May 21, 1926 IIIIIII 1 so clearly illustrate the same.

Patented 10, 1936 UNITED s rens mm a. ILEMAN, or New YORK, 1r. Ass1e1vo:s., BY mnsnn AssmNMEN'raro consonmernn asncnor'r mmcocx COMPANY, me, or NEW YORK, N. Y., a con1 o1a.e.-.

. @101: or DELAWARE rnnssunn eta-con 'My invention relates toimprovements in pressure operated-mechanism and more particularly to pressure gauges adapted to give accurate indications for comparatively low pressures or low difierences in pressures. The main object of the invention is to provide a gauge which is not only simple and eflicient in construction but also one which. is less likely to get out of order and one which is easily and readily adjusted.

Further and more specific ob ects, features and advanta es wlll more-clearly appear from th "detall description given below 'taken in connection with the accompanying 15 sheet of drawings which illustrate a gauge embodying my improvements in a preferred form thereof. Y In the drawings, Fig. 1 is a plan view of the gauge partly in section in order to more Fig. 2 is a vertical section taken on the line A-'-A of Fig. 1. Fig. 3, ,is a transverse section taken on the line :B- B of Fig. 1.- Fi 4. is a transverse section taken on the line -.-;C of Fig. 1, and Fig. 5 is a transverse 'sectiontaken on the line D-D of Fi 1. j j Referringto t e drawings, 6 represents a part of the framework comprising a base plate for. holding a pressure operated diaphragm 7. The diaphragm 7 consists of a thin sheet of metal circular in shape and soldered into a rabbeted portion of the plate 6 around the periphery as at 8. Underneath the diaphragm 7 the plate 6 is recessed at 9 so as to provide ashallow recess of redetermined depth underneath the diap ragm when the latter is in its normal position as shown on the drawings. Around the recess 9, plate 6 is provided with a circular groove 40-10 and between the groove 10 and recess 9 plate'6 is provided With a circular ridge 11. The diaphragm 7 is preferably applled to 1 the plate 6 by taking a flat circular sheet of the metal and soldering the edges to the plate 6 as at 8. Thereupon a die provided with a'ridge adapted to fit or cooperate w th i the groove 10 is pressed down upon the diaphrag'm and plate thus forcing the metal of the diaphragm into the groove 10. Thls causes the diaphragm to be stretched and tensioned over the circular ridge 11. 7 There after air may be introduced under pressure into the space between the diaphragm and plate 6 'to move the diaphragm through its diaphragm 7 anddisc 12 is a plate 13, which plate has screw-threaded in itsperiphery screws 14 and 15., which serve to adjustably space the plate 13 from the plate 6 and diaphragm 7. There are also provided screws 16 passing freely through the plate 13 at its edge and screw-threaded into the plate 6.'

Coil springs'17 surround the screws 16 between the heads thereof and the plate 13 whereby the springs 17 tend to force the plate 13 towardthe plate 6 and resiliently hold the screws 14 and firmly againstthe plate 6. By turning the screws 14 and 15 the plate 13 may be adjusted towardand from the plate 6 and diaphragm 7' so. that the-space between the diaphragm 7 and plate 13 may be thus easily adjusted. The plate 13 is provided with a shallow circular recess at 18 to accommodate the thin disc 12 on the diaphragm 7.

'19 represents, a'leaf spring fulcru'mmed on a bevel portion 20 of the plate 13 at 21. 22 represents a metal plate on the outer end of the spring 19 and a screw 23 passes loosely through theplate 22 and spring 19 and is i i screw-threaded into the plate 13 whereby upon turning the screw 23 the tension exerted by the spring 19 may be easily adjusted. At it's'inner end adjacent the center part of the diaphragm 7 the spring 19 has secured to its underneath side a button24 which bears against the plate 12 on the diaphragm 7. The button 24 passes through central aperture 25 in the plate 13v and when the parts are in position for operation, ten-- sion of the spring 19 is so adjusted by operation of screw 23 that it will force the central portion of the diaphragm 7 down substantially'to the bottom of the recess 9. In Figs.

2 and 3 of the drawings, the diaphragm,

however, is shown in its normalposition', the

v The plate spring 19 not ldown into the recess 9. g

13 is provided with .integral posts 26 to which is secured framework comprising upper plate 27 and lower plate 28 secured together by spacers 29 and screws 30.

A suitable dial 31 is secured to-the top of the.

posts 26. Surrounding the whole-is acylindrical casing member 32 secured to the. base plate, 6- by means of screws or bolts 33, around the periphery of the base plate, a packing 34 being: inserted between the two in order to provide a, substantially air or pressure tight joint. The 'casing 32 is -pro-' vided with a a transparent lass 35 securely sealed in the front endof t e casing so that the interior of the casing is made air or pressure tight.

'Journaled in the framework 27-and 28 is v a. spindle. 36 which passes-through the dial 31 and has secured on its outer end' an indicating. pointer 37. A .coil hair spring 38 having its inner end secur ed to the spindle 36 and its outer end secured to the frame member: 29 normally tends to "return the pointer 37 to its'zero position and also take up:backlash in the movement. J ournaled ona postat 39 is a se out 40 meshing with a gear 41 on the spin li 36, On the other side of the shaft 39 the segment 40 is-provided with alaterally extending arm 42. Journaled-in'the framework at 43 and 44 is a; lever member 45 having an upwardly extendin arm 46 adapted to engage the arm 42 on t e segment 40. The lever .45 is also provided =with..a

laterallyextending arm 47 extending sub stantially parallel with the diaphragm 7 and plate 13andadapted to be engaged by knife edge 48 secured to and carried by the inner end of the leaf s ring 19 adjacent the central part of the diaph nection whereby air or other fluid under pressuremay be introduced'through hole51 to the space or closed chamber on the underneath side of the diaphragm between it and the plate 6. 52 represents a similar connection whereby air or other fluid under pressure may be introduced into the space or closedchamber on the other side of the diaphra through a hole 53.

WE; only one ressure and not difference I in pressure, is to e measured, the pressure is exerted through the connection 50 an causes the diaphragm to be raised against the action of the spring 19 whereu on the button 24 and knife edge '48 are raises as viewed in r 3, causing the arm 47 of the lever 45 to e raised sllghtly whereupon the arm 46 of the lever causes a slightfoscillation of the arm 42 on the segment 40, which rotates the gear 41 causing rotation ofthe pointer 37 responsive to and in an amount corresponding to the pressure applied whereby the pressureis measured or indicated L If difl'erence in pressures is to be measured then the greattween sa1d pressures.

ragm. 50 represents a coner is applied through the connection 50 while the lesser pressure is applied through the connection. 52- to the upper side of the diaphragm'as viewed inFig; 3 whereupon the movement of thediaphragm will be controlled by and responsive to the difierence be And wherever I refer' to the pressure being applied to the diaphragm or the hue side of the diaphragm, I include also the operation by such difi'erentialpressure. Thus' in operation the diaphragm 7 is, when no fluid pressure is applied thereto,;maintained on one side of its normal position by the spring 19 and when operated yj pressure to be measured is moved back to its normal posltion and even to the other side of its normal position against the action of the spring 19. a .v

Should for any reason the pressure'applied to the diaphragm be greater than tllat for which theapparatus was intended the dia-' phragm will come against the plate 13 which actsasf a stop therefor and'tlius prevents such excessive pressure from operating the indi eating mechanism beyond the rangefor which it was designed and so injuring the same.

Likewise in measuring differential pressures,

should for any reason the flow of. fluid through the connection 50 be sto ped while permittin' high pressure to. e exerted through t e connection 52, then an excessive pressure would be appxlied to the diaphragm on the opposite side t from doing injury thereto becausethe surface of the recess 9 in the plate '6 acts as a phragm in this direction." I find that by using as ring such as the leaf spring 19, acting ont e diaphragm in oppositionto the ressure being measured, that the instrument ecomes much'more reliable and satlsfactory in operation.

In order that the-range of movement of the 'pointer may be adjusted for any given'range. of movement of the diaphragm, it is. only. necessary to move the. spring 19 laterally over I the diap ragm slightly so that the knife edge 48 will be moved. toward or from the-axis of the lever-J45. For this purpose the leaf spring l9.is' slotted on its outer end and the screw 23 and pivot pin 21 pass throughsuch slot so that by ,loosening the'screw 23 the spring '19 may be moved over the diaphragm in a direction substantially parallel thereto so that the knife edge 48 will engage the lever arm 47 at'a greater or less distance from the axis of the lever and thus any given'movementof the diaphragm will produce a'less or.

ereof, but is prevented. I

stopfor any exeessive'movement of the diaince the indicatb simply moving the plate 13toward or from t e plate 6 and diaphragm 7. Thus 13%81111- ply raising the late 13 as viewed in ig. 3

y operation the screws 14 and 15, the spring19 which causes the button 24 to be pressed against the diaphragm will drop with respect to the lever arm 47 thus permittingthe lever arm 47 to rotate slightly and bring the indicating pointer to any. desired position.

In orderthat such adjustment may be made without removing the casing 42 and while pressure is being'applied to the inside of the casing, I have shown in Fig. 3 a screwthreaded member 55 screw-threaded into the side or edge of the plate 6 and provided with a beveled portion at 56 adapted to engage a plunger 57 freely movable in a hole underneath the screw 14 whereby by'screwing in the screw 55 the bevel 56 will engage plunger 57 and cause the same to be raised as viewed in Fig. 3, thus engaging the screw 14 and raising the plate 13 onone side thereof which causes the knife edge 48 to be moved down underthe' action of the spring 19, with respect to the lever 45 and so bring about the desired adjustment of the pointer 37 By unscrewing the screw 55 adjustment maybe especially when stretched in position and a made in the opposite direction. It will be understood that when the apparatus is ready for operation and with no pressure applied, that the spring 19 will cause the diaphragm,

to assume a convex shape extending into the recess 9, and when the pressure to be measured is applied, the spring controls the extentof motion 'of the diaphragm for any given pressure, and if the pressureapplied is suificient the diaphragm will be moved back to its normal position or beyond to assume a convex shape.

by the application of excessive pressure. I find that in such an apparatus a diaphragm having a substantially flat, plane and non.- corrugated surface gives excellent results and conditioned as described.

While I have described my improvements in great detail and with respect to a preferred form thereof, 1 do not desire to be limited to such details or form since many changes and modifications may be made and the invention embodied in widely different forms without departing from the spirlt and scope thereof in its broader aspects; hence I desire to cover all modifications and forms coming within the language or scope of any one or more of the appended claims.

What I claim as new and desire to secure by Letters Patent is I 1. A pressure gauge having in combmas tion a diaphragm, means holdingthe dia-: phragm and-applying pressure to be meas ured to one side of the diaphragm, a frame But the diaphragm is limited in its movement in both directions by the plates 6 and 13 respectively sothat 1t and the indicating mechanism cannot be damaged s de of the diaphragm, a frame on the other side of the diaphragm, indicatingmechanism carrled by said frame and operated'by the diaphragm responsive to variations in the pressure applied thereto, and-means for adj-ust'ing the position of said frame toward and from said holding means and diaphragm to adjust the reading of the indicating mechanism, and a spring carried by said holding means and acting 'on said diaphragm in opposition to said pressure.

. 3. A pressure gauge having in'combination a diaphragm, means holding the diaphragm and applying pressure to be measured to one side of the diaphragm, a plate en the other side of the diaphragm, indicating mechanism carried by said plate and operated by the diaphragm responsive to variations in the pressure applied thereto, and means for adjusting the position of said plate toward and from said holdingmeans and diaphragm to adjust the reading of the indicating mechanism,.said plate carrying a surface acting as a stop for the diaphragm to prevent excessive pressure from injuring the indicat-' ing mechanismh 4; A pressure gauge having a combination a diaphragm, means holding the diaphragm and'applying pressure to be measured to one side of the diaphragm, a plate on the other side of the diaphragm, indicating mechanism carried by said plate and operated by the diaphragm responsive to variations in the pressure applied thereto, means-for adjusting the position of said plate .towardand from said holding means and diaphragm to adjust the reading of the indicating mechanism, said plate carrying a surface acting as a stop for the diaphragm to prevent excessive pressure from injuring the indicating mechanism, and a spring carried by said holding means and acting on said diaphragm in opposition to said pressure.

5. A pressure gauge having in combination a diaphragm, means holding the diaphragm and applying fluid under pressure to both sides thereof, indicating mechanism operated by the diaphragm, a casing enclos- 1 ing said indicating mechanism and confining the fluid under pressure on one side of the diaphragm, and means operable from. the outside of saidcasing'for adjusting the reading of the indicating mechanism with outrelieving pressure ofthe con? fined by the casing. i g

' 6. p A pressure 'gaugehavingin combination a diaphragm, means holdingthe diaphragm and applying fluid under pressure to both sides thereof, a frame carried by said means,

indicatingmechanism carried by said frame antioperated by the diaphragm, a casing en-- closing saidindicating mechanism and confining the'fluid under pressure on one side of the diaphragm, and means operable from the outside of said casing for adjusting the nism 4 on said diaphragm c on each side of the diaphragm,

by fluid under pressure sure tio Y A pressure gauge having fluid under position of the frame and indicating mecha- 7,

toward and from the holdingmeans to adjust the reading of the indicating mechanism without relieving the pressure of the fluid confined by the casing.

ressure gauge having in combinaa diaphragm, means for. applying presto be measured to said diaphragm, said diaphragm having a substantially'flat and non-corrugated surface, a leaf spring acting at the central part there of in opposition to said pressure, means cartion,

ried by the gauge whereby the pressureexerted by the spring on the diaphragm may be adjusted,

when unopposed by said ressuie, said pressure acting to'move the 'aphragm back to its normal plane, indicating mechanism operated by said diaphragm responsive to variations' in the pressure applied thereto, and means having relatively fixed surfaces, one on each side of the diaphragm and posi tioned'to limit its movement in each direcphragm oppositethat to which the high pressure 1s applied and acting as a stop forthe diaphragm should excessive pressure be ap-. plied to the diaphragm acting to force it in I that direction. i

9. Apressure gauge having in combination a diaphragm, means holding the diaeach side of the diaphragm, means whereby fluid under pressure may be introduced into one of said chambers, andmeans whereby fluid under pressure may be introducedinto weasel sides of said diaphragm ring actin to force said diaphragmfto war?the high Enid pressure side when no fluid pressures are 'hp-' .plied, and indicatingmechanism operated by i the diaphragm for ndicatin the difference in pressure on opposite si es of the diaphragm, said holdin on the side of the f to "which the high pressure is applied and acting as a stop for the diaphragm excessive pressurebe applied to the diaphragm. In testimony whereof I have name to this specification. I

' V EMIL A, ILEMAN- signed my sa1d spring acting to move the i diaphragm 0 one side of its normal plane should means having a surface iaphragm opposite that Ill! T phragm and forming closed chambers oneon' 00 the other of said chambers, whereby difl'er'ent fluid pressures are applied to the opposite 

